부산대학교 도서관

The magnetization roasting of hematite with two particle sizes was performed to investigate the growthbehavior and kinetics of magnetite. The magnetite exhibited comparable growth trends throughout themagnetization roasting process at different roasting temperatures, and enhancing the roasting temperaturecan facilitate the growth of magnetite. The nascent magnetite nuclei appeared acicular, predominantlydeveloped along the edges and fissures of the hematite particles before progressively growinginward. Moreover, the temperature stress and magnetite formation led to the loose and porous structureof the nascent magnetite particles. The growth kinetics demonstrated that the growth process of magnetitecould be divided into induction period and growth period based on the different growth rates. For the same hematite sample, the growth rate of magnetite in the induction period was lower than thatin the growth period. The magnetization roasting of hematite with a smaller particle size may be completedin a shorter time, even if increasing the particle size of hematite can accelerate the growth rateof magnetite. The growth kinetic models were established based on the parabolic law, and the reliabilityof describing the growth process of magnetite was verified by comparing the predicted values with theexperimental values.